Printing press throwoff mechanism and method



April 24, 1962 R. E. LINDEMANN PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed- March 2, 1959 8 Sheets-Sheet 1 INVENTOR.

floss RT E. LINDEN/INN BY ,QWQ,

April 24, 1962 R. E. LINDEMANN 3,030,384

PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2, 1959 8 Sheets-Sheet 2 l 35 33 I @fiz I50 W s4 /9I f 22, L. 32 I 90 I o INVENTOR. ROBERT E. INDEMAA/N BYW M v I QM;

A 770 RA/EYS April 24, 1962 E. LINDEMANN 3,030,884

PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2, 1959 8 Sheets-Sheet 3 INVENTOR. ROBERT E. L INDEMANN QMJ$W ATTORNE Y6 April 24, 1962 R. E. LINDEMANN 3,030,884

PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2. 1959 8 Sheets-Sheet 4 INVENTOR. Roe/5R7 E. LINDEMANN ATTORNE Y5 April 24, 1962 R. E. LINDEMANN 3,030,834

PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2, 1959 8 Sheets-Sheet 5 INVENTOR. ROBERT E. Ll/VDEMA NN ATTORNEYS April 24, 1962 R. E. LINDEMANN PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2, 1959 8 Sheets-Sheet 6 i l i 5? E I IN VEN TOR.

ROBERT E lawn/ANN Tm/wg r:

A ril 24, 1962 E. LlNDEMANN 3 PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2, 1959 8 Sheets-Sheet 7 L111: 11 lill'll I IN V EN TOR. Ros ER T 5. [mas/-14 NN ATTORNEYS April 24, 1962 R. E. LINDEMANN 3,030,884

PRINTING PRESS THROWOFF MECHANISM AND METHOD Filed March 2, 1959 8 Sheets-Sheet 8 fie. INVENTOR.

ROBERT E. ZINDEMA/V/V MM, Q

A TTORNE rs All atent 3,030,884 PRINTING PRESS THROWOFF MECHANISM AND METHOD Robert E. Lindernann, Medina, Ohio, assignor to Harris- Intertype Corporation, Cleveland, Ohio, a corporation of Delaware Filed Mar. 2, 1959, Ser. No. 796,444 26 Claims. (Cl. 101-218) The present invention relates to a throwoif mechanism and method for the cylinders of a sheet-fed printing press and, particularly, to the throwolf mechanism and method thrown off from the plate cylinder and then from the impression cylinder in sequence. Then, when the cylinders are to be again thrown on, the blanket cylinder is first moved into engagement with the plate cylinder, and then into engagement with the impression cylinder. The sequential throwoif and throwon of the blanket cylinder is accomplished by supporting the blanket cylinder with double or nested sets of eccentrics, the shaft of the cylinder being carried by inner eccentrics which are rotatable Within outer eccentrics rotatably mounted in side frames of the press. In the preferred type of eccentric throwoff, both sets of the eccentrics are moved in unison about the axis of rotation of the outer eccentrics to throw off the blanket cylinder from the plate cylinder and the inner eccentrics are then moved relative to the outer eccentrics to throw off the blanket cylinder from the impression cylinder.

In other types of throwoff mechanisms, one set of cocentrics alone is rotated to effect the throw-off of the blanket cylinder from the plate cylinder and a different set of eccentrics rotated to throw the blanket cylinder from the impression cylinder.

The impression cylinder of a sheet-fed printing press has a plurality of grippers associated therewith in a cylinder gap to grip the leading edge of the sheet to be printed and clamp the same to the impression cylinder. The blanket cylinder is provided with :a corresponding gap which is located so as to register with the gap in the impression cylinder as the cylinders arerotated. Similarly, the plate cylinder is provided with a gap which registers with the gap in the blanket cylinder during rotation of the cylinders. The gap in the plate cylinder provides a space for fastening the printing plate to the cylinder.

It is desirable to start the cylinder throwoif movement and to complete the cylinder throwon movement as the gaps in the cylinders are in registry with each other. If the blanket cylinder is thrown off or on relative to the so that these movements may be accomplished with respect to its cooperating cylinders when the cylinder gaps are opposite each other.

The throwon movement may be initiated before the gaps are in registry with each other and the throwoff movement can be completed after the gaps have passed each other, as long as the cylinder surfaces are clear of each other when the gaps are not in registry. There is a limited time required for throwing on and throwing off the cylinders during which the gaps must be in registry with each other if a sheet is not to be spoiled because of the throwon and throwoff operations. For newer highspeed presses, the gap size and/or the rate of throwofii' and throwon must be increased to accomplish the throwolf and throwon movements wtihout spoiling a sheet. There is, however, a practical limit, due to the inertia loads involved, to the rate at which the throwon and throwofi of the cylinders of the printing press can be effected. As a result, it has heretofore been necessary, after this practical limit has been reached, to increase the gap size as the speed of the press is increased to provide adequate time for throwon and throwofl Without loss of printed sheets or the printing of the surface of the impression cylinder during such operations.

An important object, therefore, of the present invention is to provide a new and an improved method and apparatus for throwing off and on a cylinder of a sheetfed printing press, particularly a high-speed press, which enables the cylinders to be thrown off and on without partially printing a sheet and the cylinders to have relatively small cylinder gaps for a given press speed and for the throwoif and throwon to be accomplished without subjecting the throwoff mechanism to unduly high inertia loads.

Another object of the present invention is to provide a method of and an apparatus for throwing off and on a first cylinder of a sheet-fed printing press which runs in engagement with a second cylinder of the press during the printing operation, which method and apparatus enable the speed of the press to be increased without increasing the size of the gaps in the cylinders to provide adequate time to complete the throwon or throwofi movements of the first cylinder and without decreasing the time period for accomplishing the throwon and throwofi movements.

Another object of the present invention is to provide a press throwoif mechanism wherein the throwon and throwolf movements of one cylinder relative to another are initiated at different points in the press cycle and in which parts of the throwoff movement and the throwon movement occur over common overlapping portions of the press cycle.

A still further object of the present invention-is to provide a new and an improved double eccentric throwoff mechanism for moving a first cylinder to sequentially disengage or engage the cylinder with two different cylinders impression cylinder when the gaps are opposite each with which the first cylinder runs in engagement during the printing operation; in which mechanism inner and outer eccentrics supporting the first cylinder are sequentially rotated to move the first cylinder sequentially to or from its cooperating cylinders, with the eccentrics being interconnected by *a toggle linkage having overcenter locked positions which effect movement of the eccentrics as a unit when one eccentric is moved, and which is moved between the overcenter locked positions to move the inner eccentric relative to the outer eccentric.

A further object is to provide a double eccentric throwoff mechanism as described in the preceding object in which the position of the first cylinder relative to one of the cylinders may be adjusted through a worm and wormwheel mechanism including an element rotatably supported by the frame and an element rotatably carrier by the outer eccentric and connected to move the inner eccentric relative to the outer eccentric through the toggle mechanism.

It is also an object :of the present invention to provide, in a double eccentric throwotf mechanism of a printing press, a novel and an improved adjusting mechanism for adjusting the position of one eccentric of the throwoff mechanism relative to the other eccentric, such adjusting mechanism being constructed to be carried by and moved with the eccentrics during throwoff movements while retaining the adjustment.

Still another object of the invention is to provide a novel drive means for the adjusting mechanism, which drive means is capable of compensating for movement of the adjusting means relative to operating means therefor carried by the press frame.

Further objects and advantages of the present invention will be apparent from the following detailed description thereof made with reference to the accompanying drawings forming a part of this specification and in which:

FIG. 1 is a fragmentary side elevational view of a printing unit of a printing press embodying the present invention and with parts thereof cut away;

FIGS. 2, 3, 4 and 5 are simplified views corresponding to FIG. 1 having certain parts omitted and showing the throwoff mechanism and the press cylinders in their various positions corresponding to different conditions of throwon and throwoff, respectively;

FIG. 6 is a detailed view showing the cam followers and levers for operating one set of eccentrics of the throwoff mechanism and looking from line 66 of FIG. 7;

FIG. 7 is a view taken approximately along line 7-7 of FIG. 6;

FIG. 8 is a fragmentary enlarged view looking approximately from line 88 of FIG. 1;

FIG. 9 is an enlarged view looking approximately from line 99 of FIG. 1;

FIG. 10 is a view taken approximately along line 10- 10 of FIG. 3; and

FIG. 11 is a view of the printing unit shown in FIG. 1 looking at the opposite side of the press.

While the present invention may be embodied in the throwofi mechanisms of various types of printing presses, such as letter presses, it is particularly useful in a rotary lithographic offset printing press having plate, blanket and impression cylinders and in which the blanket cylinder is supported in side frames by inner and outer eccentrics so that it can be thrown on and off in sequence with respect to the plate and impression cylinders.

Referring to the drawings, the invention is disclosed as embodied in a rotary oifset printing press having a plate cylinder 10, a blanket cylinder '11 and an impression cylinder 12. The cylinders are arranged generally along a vertical line with the blanket cylinder being offset to one side of the line and having its lower periphery in running engagement with the impression cylinder 12 and its upper periphery in running engagement with the plate cylinder 10. The cylinders 10, 11 and 12 each have a gap 13 therein and the gaps are disposed so that adjacent ones will register as the cylinders are rotated.

The blanket cylinder 11 is supported by means comprising pairs of inner and outer eccentrics on opposite sides of the prms, each pair being supported by one of the press side frames 16. The inner and outer eccentrics on one side of the press are designated by the reference numerals 14, 15, respectively, and on the other side by the reference numerals 14', 15. The structure and manner of operation of the eccentric pairs are substantially duplicates of each other and for the sake of simplicity the present invention will be described primarily by reference to the eccentrics 14, 15. The inner eccentric 14 carries a shaft 17 of the blanket cylinder 11 and is supported for oscillation within the outer eccentric 15 and the outer eccentric oscillates in the frame 16 about a center which is offset from the axis of the shaft of the blanket cylinder and from the axis of the inner eccentric 14. The structure of the inner and outer eccentrics, per se, is not shown or described in detail since such eccentrics are well known to those skilled in the art. Suffice it to say that the outer eccentric 15 when rotated clockwise from the position corresponding to that shown in FIG. 1 effects movement of the blanket cylinder 11 toward the right and downwardly to move the blanket cylinder out of engagement with the plate cylinder 10 while the engagement of the blanket cylinder with the impression cylinder 12 is maintained. In the illustrated embodiment, the inner and outer eccentrics move as a unit when the outer eccentric is rotated to move the blanket cylinder out of engagement with the plate cylinder 10. After the blanket cylinder has been moved out of engagement with the plate cylinder, it is then moved out of engagement with the impression cylinder 12 by rotating the inner eccentric 14 relative to the outer eccentric 15 and the frame of the press and in a clockwise direction, as viewed in FIG. 1. The cylinders are subsequently thrown on by first moving the outer eccentric and, in the illustrated embodiment, the inner eccentric counterclockwise, as viewed in the drawings, relative to the frame to throw the blanket cylinder to the plate cylinder, as is shown in FIG. 4, and then by moving the inner eccentric counterclockwise relative to the outer eccentric and press frame to throw the blanket cylinder to the impression cylinder.

The eccentrics 14, 15 respectively carry brackets 18, 20 to which the operating mechanism for rotating the eccentrics is connected. The outer eccentric 15 and the inner eccentric 14 are interconnected by a toggle linkage 21 connected between the bracket 18 and the bracket 20. The toggle linkage 21 is generally aligned with the direction of oscillation of the eccentrics and, therefore, causes the eccentrics to move together when one is rotated. The toggle linkage 21 comprises a toggle link 22 pivoted at one end to the bracket 18, a toggle link 23 having one end pivoted to the other end of link 22 by a pivot pin 24, the other end of link 23 being pivoted by a pin 23a to an arm 25 rockably supported on the bracket 20 by a pin 26. The arm 25 is normally held against movement relative to the bracket 20 by mechanism to be described in detail hereinafter.

The toggle linkage 21 forms a force transmitting connection between the eccentrics 14, 15 so that one moves with the other and so that the inner eccentric can be rotated relative to the outer eccentric by moving the toggle linkage 21 from its overcenter position shown in FIGS. 1 and 2 through center to its position, shown in FIG. 3 to effectively shorten the toggle linkage. A toggle actuating link 28 is pivoted to the pin 24 of the toggle linkage 21 and is endwise movable to supply the force necessary to actuate the toggle linkage 21 between its positions shown in FIGS. 1 and 3. The link 28 also prevents the linkage 21 against collapsing outwardly from the positions of FIGS. 1 and 3.

The eccentrics 14, 15 are oscillated to effect the throwon and throwoff of blanket cylinder 11 in timed relation to the operation of the press by reciprocating respective toggle shift or throw bars 30, 31. The toggle shift bar 31 for effecting rotation of the outer eccentric 15 is pivoted at one end to an arm 32 of a bell crank lever 33 keyed to a rockshaft 34 having an axis parallel to that of the blanket cylinder. The shaft 34 is rotatably supported by the frame of the press outwardly of the right-hand side of the blanket cylinder, as the latter is viewed in FIG. 1, and extends between the press side frames 16.

The bell crank lever 33 includes an arm 35 extendcounterclockwise direction.

ing approximately at right angles to the arm 32 to which the shift bar 31 is connected. The arm 35 is connected to the bracket 20 through a link 36 which is pivoted at one end to the outer end arm 33 and at its other end to a link 37. The link 37 has one end pivoted to the bracket 20 carried by the eccentric 15 by a pin 38 and the other end pivoted to a relatively stationary member 40 by a pin 41. The link 36 connecting the bell crank lever 33 and the link 37 intermediate its ends but close to the connection of link 37 to the bracket 20 by a pin 42. The arm 35 and the link 36, in effect, form a toggle linkage which is moved through center when the arm 35 and the shaft 34 are rocked by the reciprocation of toggle shift bar 31 to rock the bell crank lever 33.

The limit positions of the bell crank lever 33 are shown in FIGS. 1 and 2 and the bell crank lever 33 is rockable between these positions by operating the shift bar31. The limit positions of the bell crank lever 33 are determined by setscrews 43 disposed on opposite sides of the shaft 34 and are each adapted to engage a respective lug 44 on the bell crank lever 33 when the lever is in a respective one of its limit positions to limit further movement of the bell crank lever in the direction of the setscrew. When the bell crank lever 33 is rocked from the limit position shown in FIG. 1 to the limit position shown in FIG. 2, the toggleconnection formed by the arm 35 and link 36 is effectively shortened and the link 37 is rocked to effect oscillation of the bracket 20 and, in turn, the eccentric 15 in a clockwise direction, and when the bell crank lever 33 is rocked from the limit position shown in FIG. 2 to the limit position shown in FIG. 1, the eccentric 15 is moved in a The eccentric 15 is in its throwon position when the bell crank lever 33 and shift bar 31 are positioned as shown in FIG. 1 and in its throwoif position when the bell crank lever and shift bar are as shown in FIG. 2.

The shift bar 31 is moved endwise between two positions to pivot the bell crank lever 33 and effect the throwon and throwoif of the blanket cylinder 11 with respect to the plate cylinder through the operation of a cam 46 fixed to and rotatable with the shaft of the plate cylinder 10. The cam 46 effects the reciprocation of two throw pins 47, 43 which are adapted to engage and actuate the shift bar 31 in its throwoif and throwon movements, respectively. The throw pin 47 for efiecting the throwoff movement of the shift bar 31 is carried at the end of an arm 53 of a bell crank lever '51. The bell crank lever 51 is pivoted in the frame by a platelike bracket 57 and has an arm 52 extending approximately perpendicularly to the arm 50 supporting the throw pin 47 and carrying on its outer end a cam follower 53 which is adapted to ride on the cam 46. The throw pin 48, for effecting the throwon of the cylinder 11, is supported by a rocker member 55 which also mounts a cam follower 56 adapted to ride on the cam 46 and effects a rocking or reciprocation ,of the rocker member 55 upon rotation of the cam. The bell crank lever 51 and the rocker member 55 are pivoted to the inner side of the plate-like bracket 57. The bracket 57 has feet 57a, 57b at its ends which are bolted to the adjacent press side frame and space the major part of the bracket from the side frame.

To effect reciprocation of the bell crank lever 51 and the rocker member 55, and, in turn, the throw pins 47, 48, respectively, the cam 46 is provided with a high portion 46a and a low dwell portion 46]) disposed on opposite sides of the cam and joined by cam portions 46c and 46d which efiect the work and return strokes of the throw pins. When the cam followers are riding on the side portion 460 from the low portion to'the high portion, the throw pin 47 moves inwardly toward the cam 46 and the throw pin 48 moves outwardly, and when the cam followers are riding on the portion 46d from the high portion to the low portion, the throw pins 47,

48 will be moving outwardly and inwardly, respectively. It can be seen that the cam 46 effects reciprocation of the throw pins 47, 43 between limit positions and that the portion 46b provides a dwell. The cam followers 53, 56 are biased into engagement with the cam 46 by a spring 58 disposed about a rod 59 extending between bosses 590 formed respectively on the bell crank lever 51 and the rocker member 55. The spring 58 is a compression spring and the bosses 59a are located on the sides of the pivots for their corresponding supporting members so that the spring urges the bell crank lever 51 and rocker 5S counterclockwise about their pivots or toward the cam 46, as viewed in FIG. 1.

The throw pins 47, 48 are disposed on the opposite sides of the toggle shift bar 31 and the toggle shift bar 31 has recessed shoulders 60, 61 on opposite sides thereof disposed to be engaged by the throw pins 47, 48. The shoulder 60 faces in the direction of outward movement .of the throw pin 47 and is adapted to be engaged by the latter when the pin is moving inwardly toward the cam 46, while the shoulder 61 faces in the direction of inward movement and is adapted to be engaged by the throw pin 48 when the latter is moving outwardly. The shoulder 60 is located so that when the shift bar 31 is moved slightly about its pivot in a counterclockwise direction from its position of FIG. 1, the shoulder is just inside of the limit of the outward movement of the pin 47 and is engagement by the pin 47 as it moves inwardly to pull the shift bar 31 to its FIG. 2 throwoff position. On the other hand, the shoulder 61 is located so that when the shift bar 31 is moved clockwise about its pivot from its FIG. 3 position, the shoulder 61 will be engageable by throw pin 43 just after it begins its outward movement so that the throw pin will push the shift bar 31 to its FIG. 1 throwon position as the pin 47 moves outwardly. The spacing of the throw pins 47, 48 and width of the shift bar 3 1 are such that only one of the throw pins 47, 48 can engage the shift bar at any given time and the particular pin is selected by urging the shift bar 31 about its pivot toward the particular pin. Any conventional means operated in response either to manual operation or automatic detection that a malfunction of the press is occurring, may be used to actuate the bar 31 between its two positions. The operating means may be connected to the bar 31 through a rod 62. If the shift bar is urged toward the pin 47, the pin when it starts its inward movement will engage the shoulder 63 and move the shift bar endwise to its throwoff position. The movement of the bar 31 to throwoif position effects the throwoff of the blanket from the plate cylinder and returns the shoulder 61 to where it may be positioned, by swinging the bar, to be engaged by the pin 48 as it begins its outward movement. After the bar is in its throwofi position (FIG. 2), the pin 47 will reciprocate along the side of the bar 31 inwardly of the bar from the shoulder 63 without further engaging the shoulder 63 to move the bar 31. The outer end portion of the bar 31 is formed with an inclined portion 63 leading to the shoulder 63 and against which the throw pin 47 will ride when the shift bar 31 is initially urged into engagement with the pin 47 if the pin 47 is at that time disposed outside of the shoulder 69.

The shoulder 61 and the throw pin 43 cooperate in the same manner as described for the throw pin 47 and shoulder 6i) to move the shift bar 31 to its thrown position if not already so positioned, when the shift bar 31 is urged into engagement with the pin 48. The movement to throwon position effects the throwon of the blanket cylinder with respect to the plate cylinder and returns the shoulder 63 to a position where it may be engaged by the pin 47 when the bar is subsequently urged toward the pin 47. After the shift bar is in its throwon position, the pin 43 will reciprocate on the side of the bar outside the shoulder 63 and designated by the reference numeral 64 without effecting movement of the shift bar, since the shoulder 60 will be positioned at the outer limit of the outward movement of the pin 43. The stroke of the shift bar produced by each pin is substantially the same so that the stroke produced when one pin engages its corresponding shoulder returns the other shoulder to its limit position at the beginning of its work stroke.

Since the followers 53, 56 ride on the same cam, the reciprocating movement of the throw pins 47, 48 upon rotation of the cam will basically be the same. However, the followers 53, 56 are angularly displaced from each other on the cam and so the reciprocating movements of the pins 47, 48 will be out of phase with each other. The movements of the pins 47, 48 are timed so that the pin 47 begins its inward or throwolf movement immediately after the leading edges of the gaps in the plate cylinder and blanket cylinder have passed each other, and the length of the portion 460 is preferably such that the throwoff movement takes place over the length of the gaps and is completed after the trailing edges of the gaps have passed each other. The amount of throwofi accomplished by the time that the trailing edges of the gaps have passed each other is such that the cylinders and 11 are clear of each other. It will be noted that the cam follower 53 rides on the cam 46 in advance of the cam follower 56 and, therefore, the throwon movement is initiated in the press cycle in advance of the throwoff movement. The cam follower 53 is so positioned that the throwon movement begins before the leading edges of the gaps in the plate and blanket cylinders pass each other and is completed while the gaps are opposite each other and, preferably, just before the trailing edges of the gaps pass. The throwon movement is such that the blanket cylinder is moving toward the plate cylinder before the gaps register, but the plate and blanket cylinders still have clearance at the time the leading edges of the gaps pass each other. Since the throw pins 47, 48 are on different sides of the pivots of bell crank lever 51 and rocker member 55, respectively, the throwon and throwoff movements of pins are effected by the same portion 460 even though the pins move in opposite directions in their throwon and throwoff strokes.

The outer eccentric 15 may be adjusted, in the illustrated embodiment, relative to the press frame by adjusting the stationary pivot 41 for the link 37. The link 37, as described above, is pivoted to the member 40 and the member 40 is supported from the bracket 57 by a turnbuckle type of connection 68 which when operated moves the member 40 and the pivot pin 41 laterally.

From the foregoing description, it can be seen that throwon is initiated and throwoff completed outside of the portion of the cycle when the gaps are opposite each other and that the portions of the cycles of the press allotted to throwon and throwoff overlap each other within the gaps.

As described above, the inner eccentric 14 is actuated to throw on and to throw off the blanket cylinder 11 with respect to the impression cylinder by shifting the toggle actuating link 28 endwise to operate the toggle linkage 21 between positions on opposite sides of dead center in throwon and th-rowoff movements. The mechanism for moving the link 28 endwise is substantially the same as that for effecting the movement of the bracket to rotate the outer eccentric 14 and includes the toggle shift bar 30 which is pivotally connected at one end to a rocker member 70 keyed to a shaft 71 disposed outwardly of the blanket cylinder 11 below the shaft 34 and rotatably supported by the side frames 16 of the press. The rocker member 70 is connected by a pivot connection to the end of the toggle actuating link 28 remote from its connection to toggle linkage 21 and the rocker member 70 is rocked between limit positions to reciprocate the toggle actuating link 28 to move the toggle linkage 21 between its throwon and throwoif positions on opposite sides of dead center. The limit positions of rocker member 70 are determined by setscrews 76, each engageable with the rocker member to limit the movement thereof in a respective direction.

The toggle shift bar 30 is adapted to be pulled endwise to rock the rocker to move the toggle in its cylinder throwoff movement by throw pin 72 adapted to engage a recessed shoulder 73 on one side of the shift bar 30 and is adapted to be pushed in the opposite direction to rock the rocker 70 in its toggle or cylinder throwon movement by a throw pin 74 adapted to engage a shoulder 75 formed on the opposite side of the toggle shift bar 30 and facing opposite to the direction of throwon movement. The throw pins 72, 7 4 correspond to the throw pins 47, 48 of the first-described embodiment and are reciprocated from a cam 77 fixed to the shaft of the impression cylinder 12 and adapted to effect the reciprocation of a bell crank lever 78 which mounts the pin 72 and a rocker lever 80 which mounts the pin 74. The bell crank lever 7 8 carries a cam follower 81 adapted to ride on the cam 77, and the rocker member 80 also carries a cam follower 82 which rides on the cam 77. The operation and structure of the cam 77, the cam followers 81, 82, and the pins 72, 74 are the same as the operation of the cam 46, the cam followers 53, 56 and the bell crank lever 51 and the rocker member 55, respectively, and will not, therefore, be repeated. Suflice it to say that when the shift bar 30 is urged into engagement with the pin 74 the shift bar will, if not already so positioned, be pushed endwise to its toggle-on or throwon position and if =urged into engagement with the pin 72, will be pulled, if not already so positioned, to its toggle-off or throwoif position.

The bell crank lever 78 and the rocker member 80 are urged about their pivots in directions which move the cam followers 81, 82 into engagement with the cam 77 by a spring connection between the lever 78 and the rocker member 80. The spring connection comprises a rod 84 which is slidably received by bosses 85, 86 on the members 78, 80, respectively, and which has a spring 87 disposed thereabout and engaging, at its opposite ends, the bosses 85, 86'. The boss 85 is on one side of the pivot for the bell crank lever 78 and acts to urge the lever 78 toward the cam 77 and the boss 86 is on the side of the pivot for the member 80 which also causes the spring 87 to urge the rocker member 80 to move toward the cam 77, the spring 87 being a compression spring.

It will be noted when rocker member 70 is in a limit position, the setscrews prevent movement of the rocker member, and, in turn, the toggle actuating link 28 in a direction to permit a collapsing of the toggle linkage 21. This renders the toggle linkage effective as a force transmitting connection between the eccentrics 14, 15.

The shift bar 30 is connected by a yieldable connection to the bracket 20 so that when the eccentric 15 is rotated to throw off the plate and blanket cylinders 10, 11, the shift bar 30 is urged into engagement with the pin 72 to throw off the blanket and impression cylinders 11, 12 in a later portion of a press cycle, and when the eccentric 15 is rotated to throw on the cylinder-s 10, 11, the shift bar 30 will be urged into engagement with pin 74 to effect the throwing on of the cylinders 11, 12, also in a later portion of a cycle. In FIG. 2, throwoff of the blanket cylinder from the plate cylinder has been effected and the bar 30 has been urged to its throwoff position by movement of bracket 20 to initiate throwoff of the blanket cylinder from the impression cylinder. 'FIG. 3 illustrates the relative positions of the parts of the throwoif mechanism upon completion of throwoif movements of the blanket cylinder from both the plate and impression cylinders, while FIGS. 4 and 5 illustrate the relative positions during throwon. In FIG. 4, the throwon of the blanket cylinder with respect to the plate cylinder has been shown as completed and the shift bar 30 has been urged into engagement with the throw pin 74 which is shown in its position just before starting its throwon movement. The follower 82 is on the low dwell portion of the cam 77. The throwon of cylinder 11 with respect to cylinder 16 was initiated by urging the shift bar 31 into engagement with the pin 48. In FIG. 5, the pin 74 has completed its throwon movement and the blanket cylinder 11 is in running engagement with both the cylinders 11), 12.

The connection between the bracket 21? and the shift bar 30 comprises a rod 90 having one end pivotally connected to a triangular bracket 91 fixed to the bracket 20 carried by the eccentric 15 and the other end connected to the shift bar 31) by a noddle pin type connection comprising a head 92 which receives the rod 90. See FIG. 8. A flanged sleeve 93 is slidably disposed Within the head 92 and about the rod 911 and is slidable relative to the head and rod. The sleeve 93 has a flange at one end which engages the end of the head 92 facing the bracket 20 and the sleeve extends from the other end of the head 92 along the rod 911 and has a nut 94 threaded onto its outer end. The rod 90 extends through sleeve 93 and has a pair of nuts 95 threaded onto the outer end, which abut the adjacent end of the sleeve 93. The head 92 is biased to a predetermined position on rod 90 by a spring 96 disposed between the nut 94 on the sleeve 93 and the head 92 and a spring 97 disposed about the rod 90 on the other side of the head and engaging the flange on sleeve 93 and a collar 98 on the rod 90. The head 92 of the noddle pin is pivotally connected to the bar 30 by its bearing pin 99 received in an opening in the shift bar. When the rod 90 is pushed by the bracket, the collar 98 acts through the spring 97 and yieldingly pushes the head 92, and, in turn, the shift bar 30, in a direction away from the bracket 91 and toward the throw pin 72, and when the rod 90 is pulled, the nut 95 acts through the spring o to yieldingly urge the head 92 and, in turn, the toggle shift bar 30 toward the throw pin 74.

The rod 91] is connected to the triangular bracket 91 by a manually operable, quick-release connect-ion designated generally by the reference numeral 1%. The quickrelease connection 101) permits the rod 911 to be disconnected from the triangular bracket @1 and when this is done, the blanket cylinder 11 may be thrown off or on with respect to the plate cylinder 10 without effecting sequential operation of the blanket cylinder 11 with respect to the impression cylinder 12.

The quick-release connection 1% comprises a connecting or latching pin 1111 slidably supported by a boss 1112; formed on the triangular bracket 11 and having an axis generally perpendicular to the rod 90. The rod 90 extends along the base of the boss and has a flattened rounded end portion 103 adjacent the base of the boss, and the end portion 1113 has an opening 1114 for receiving the pin 101. The pin 131 extends through a closed end of the boss 1112 remote from the base thereof to extend outwardly of the boss. A ball handle 1115 is fixed to the pin 1111 at its outer end and forms a handgrip for effecting movement of the pin. The boss 102 is counterbored as indicated at 1-116 and a spring 1118 is disposed within the counterbore 106 and about the pin 101 and bears on a plate 1111 fixed to the pin 1111 tourge the latching pin toward the rod 90. The spring is located between the bottom of the counterbore 1116 and the plate 11%. The pin 101, however, may be lifted against the action of the spring 1118 to move the pin clear of the opening 1114 in the rod 911. When the pin is clear of the opening 104, the boss 1112 and the rod 911 may be moved relatively to each other and, effectively, the rod 961 is disconnected from the triangular bracket 91. The pin 1111 is preferably provided with a cross pin in the form of a lug 111 which is disposed to ride on the outer end of the boss 1112 when the pin 1&1 is clear of the rod 111 and is adapted to be received in a slot 1112 opening into the outer end of the boss to permit the pin to be moved into the opening 1114 in the rod 911. The latching pin may be rotated when disposed outwardly of the boss to position the lug 111 in alignment with the slot 112, or if in 19 alignment with the slot 112, to position the lug 111 to engage the outer end of the boss 102.

It is desirable to be able to effect adjustment of the inner eccentric 14 With respect to the outer eccentric 15 to adjust the printing pressure of the blanket cylinder to the impression cylinder and to compensate for various paper thicknesses. The eccentric adjusting mechanism of the illustrated and preferred embodiment is shown in FIGS. 1 and 8 and designated generally by the reference numeral 120. It will be recalled that the toggle linkage 21 includes the link 23 which is pivoted to the arm 25 which is, in turn, pivoted to the bracket 20 by the pivot pin 26. The position of the inner eccentric 14 is adjusted by moving the arm 25 about its pivot pin 26 which operates through the toggle linkage 21 to adjust the inner eccentric relative to the outer eccentric and its throwoff mechanism.

The arm 25 includes an arm portion 121 extending outwardly on the side of the pivot pin 26 remote from the link 23 and which has a worm gear segment 122 formed on its outer end. The Worm gear segment and the arm portion 121 are part of the adjusting mechanism and, in addition thereto, the adjusting mechanism includes a worm 123 rotatably supported in a bracket 124ifixed to the bracket 20 and having a shaft 125. The shaft 125 of the worm 123 is connected to an expansible drive means which includes a driven shaft 126 connected to the shaft 125 by means of a universal coupling 127, which may be of conventional construction as shown in FIG. 9. The driven shaft 126 is hexagonal in cross section and is received in a corresponding female recess 128 of a drive shaft 1311 so that the shafts 126, 130 may move in a tele-v scoping manner but yet transmit rotary motion. The tubular drive shaft 130 is in turn connected by a universal coupling 131, similar to coupling 127, to an operating member 132 rotatably supported in a bracket 133 fixed to the side frame of the press. The member 132 is formed with a worm gear 134 which cooperates with a worm 135 carried by a shaft 136 that may be turned by applying a crank thereto. It will be apparent that rotation of the worm 135 will effect movement of the arm 25 about its pivot and that the drive means formed by the shafts 125, 130 and the universal couplings 127, 131 allow the parts of the adjusting mechanism carried by the bracket 20 to move with the bracket 24 during throwon and throwotf movements without affecting the printing pressure setting. The adjusting mechanism holds the arm 25 against movement about its pivot except when the worm 135 is rotated in one direction or the other to effect adjustment of the inner eccentric 14.

From the above description, it will be understood that when the printing press is in operation with the blanket cylinder in running engagement with both the plate cylinder 1t} and the impression cylinder 12, the throwoff mechanism for the blanket cylinder 11 will be in the position shown in F113. 1. If it is desired to effect a throwoff of the blanket cylinder from both the .plate cylinder and the impression cylinder, the shift bar 31 is first urged into engagement with the reciprocating throw pin 4'3. The mechanism for urging the shift bar into engagement with the pin 47 has not been shown or described since such mechanism may comprise any suitable means for accomplishing this end, such means being well known to those skilled in the art. When the reciprocating pin 47 reaches or approaches its outer limit position ofits reciprocating movement, the shift bar 31 will move about its pivot to position the shoulder 60 in the path of the pin 47 as the latter moves inwardly from its outer limit position. As the pin 47 moves inwardly, it will pull the shift bar 31 to rock the bell crank lever 33 about the shaft 34 to effect clockwise movement of the bracket 20 and the outer eccentric 15 to the positions shown in FIG. 2. When the blanket and impression cylinder are on, the toggle linkage '21 between the bracket 20 on the outer eccentric '15 and the bracket 18 on the inner eccentric 14 11 is in its overcenter position shown in FIGS. 1 and 2 and the inner eccentric 14 will move with the outer eccentric 15 and the throwoff of the blanket cylinder 11 from the plate cylinder 10 will be accomplished as described hereinbefore. The relative positions of the parts when the blanket has been thrown off of the plate cylinder are shown in FIG. 2. The movement of the bracket 2% to throw off the blanket cylinder 11 from the plate cylinder 10 effects a shifting of the shift bar 30 through the operation of the rod 99 to urge the shift bar into engagement with the pin 72 as is shown in FIG. 2. When the pin 72 reaches the outermost limit of its reciprocating movement, the position shown in FIG. 2, the shift bar 30 will move to position the shoulder 73 in the path of the pin 72 as it next moves inwardly from its outer limit position. The inward movement of the pin 72 then pulls the shift bar 30 to rock the rocker member 7% about the shaft 71 to effect a breaking of the toggle linkage 21 by moving it through center and this causes rotation of the inner eccentric 14 in a clockwise manner relative to the outer eccentric 15. This effects the throwing off of the blanket cylinder 11 from the plate cylinder 12. The relative positions of the parts of the throwofi mechanism and of the cylinder when throwoff is completed are shown in FIG. 3.

As pointed out above, when the blanket cylinder is thrown off from both the plate and impression cylinders, the throwoff mechanism and the cylinders are in the positions shown in FIG. 3. When the blanket cylinder is to be thrown on, the shift bar 31 is first urged into engagement with the throw pin 48 and when the cam follower 56 rides over the cam portion 460, the pin 48 will engage the shoulder 61 on the shift bar 31 and push the bar to its throwon position as is shown in PEG. 4. The movement of the shift bar 31 to throwon position causes a rocking of the bell crank lever 33 and the shaft 34 in a counterclockwise direction, as viewed in FIGS. 3 and 4, to cause movement of the bracket 20 counterclockwise from its position shown in FIG. 3 to its position of FIG. 4. As described above, movement of the bracket 20 effects rotation of both the inner and outer eccentrics 14, 15 to throw the blanket cylinder 11 onto the plate cylinder 10.

The movement of the bracket 20 in a counterclockwise direction, as viewed in FIGS. 3 and 4, causes the rod 90 to pull the shift bar 30 to urge the shift bar 30 into engagement with the pin 74. When the pin 74 reaches the limit of its inward movement and begins to move outwardly, it will push against the shoulder 75 of the shift bar 30 and effect movement of the rocker member 70 on the shaft 71 in a clockwise direction, as viewed in FlG. 4, to move the shift bar from its position of FIG. 4 to its position of FIG. 5. The movement of the rocker member 70 moves the toggle actuating member 28 endwise to actuate the toggle linkage 21 from its throwoff position of FIG. 4 to its throwon position of FIG. to effect movement of the inner eccentric 14 with respect to the outer eccentric15 and the throwon of the blanket cylinder 11 with respect to the impression cylinder 12.

It will be noted that the shoulders 60, 61, 73, 75 with which the throw pins 47, 48, 72,-74 respectively cooperate have a hook-like shape so that the shoulders fit around their cooperating pins when engaged thereby. The strokes of the pins are such that when one of the cooperating shoulders is positioned to be engaged by the corresponding pin on its work stroke, its position is sufficiently inwardly of the limit position of the pin that the hook-like shoulder will clear the pin as the latter is moved to its proper position. The part of the operating cams 46 and 77 which effect the work stroke of the pins includes a very short, relatively steep rise portion which first rapidly moves the pins and then slows them gently into engagement with their cooperating shoulders. Referring to FIG. 1, the steep rise portion is the initial part of cam portion 46c and in the illustrated embodiment is active over approximately 15 of rotation of the cam.

Thus far, the description of the double eccentric throwoff mechanism shown in the drawings has been made with reference to one side of the press, that is, the side of the press having the throwoff actuating cams associated therewith. It is to be understood, as mentioned earlier, that eccentrics 14, 15, similar to the eccentrics '14, 15, are provided on the other side of the press for supporting the shaft 17 of the blanket cylinder. FIG. 11 shows the eccentrics 14, 15' and the mechanism for effecting rotation of the eccentrics. It will be remembered that the shafts 34, 71 are oscillated by the shift bars 31, 30, respectively, to effect the throwon and throwoff movements of the outer and inner eccentrics 14, 15. The shafts 34, 71 extend to the side frame of the press which supports the eccentrics 14, 15 and effect the rocking of arms 35', 70 keyed to the shafts 34, 71, respectively. The arm 35 is connected to a bracket 20 carried by the outer eccentric 15 by a linkage which is substantially the same as that for connecting the arm 35 of the bell crank lever 33 to the bracket 20 carried by the outer eccentric 15. The description of the linkage will not be repeated but the parts thereof have been given the same numbers as the corresponding parts of the linkage for connecting the arm 35 to the bracket 20 with a prime mark aflixed thereto. The inner and outer eccentrics 14', 15 are connected by a toggle linkage 21 which is substantially the same as the toggle linkage 21 and which is moved between overcenter positions by a member 28 pivotally connected to the arm 70 carried by the shaft 71 and which is the equivalent of the link 28 for operating the toggle 21. The member 28' and toggle 21' function in the same manner as the link 28 and the toggle 21 upon the rocking of the shaft 71 to effect the throwon and throwoff movements of the eccentric 14' and the description will not be repeated.

The link of the toggle 21' which is connected to the outer eccentric 15' has an adjustable pivot and mechanism is provided for effecting adjustment of the pivot in the same manner as the mechanism :120 effects adjustment of the pivot pin for the link 23 of the toggle linkage 21. The adjusting mechanism 120 is the same as the adjusting mechanism 120 and the description thereof will not, therefore, be repeated, and suffice it to say that the shaft 136 for the worm extends transversely of the press and mounts a worm 135 which is rotatable to operate the adjusting mechanism 120.

In the illustrated and preferred embodiment, a latching mechanism is disposed adjacent the shift bar 30 and is adapted to engage a shoulder 146 on the shift bar 30 when the shift bar is pulled endwise to its toggle-off position, as is shown in FIG. 3. The latching mechanism 145 comprises a latch member 147 supported for pivotal movement about an axis generally parallel to the shift bar and urged into engagement with the shift bar 30 by a spring 148, as is shown in FIG. 10. The latch 147 does not interfere with the movement of the shift bar 31 by the rod 90 and rides against the side of the shift bar 30 when the bar is urged into position to engage the throw pin 72, and when the shift bar 30 is moved to its position Where the blanket cylinder is thrown off the impression cylinder, it engages the shoulder 146. When the latching member 147 is engaged with the shoulder 146, inadvertent pivotal endwise movement of the shift bar 30 about shaft 71 and the corresponding movement of toggle 21 is prevented and the shift bar 30 must first be swung about its pivot to clear the latch 147 from the shoulder 146 before the shift bar can move endwise. This is done when the rod 90 is pulled to urge the shift bar 30 into engagement with the throw pin 74.

The preferred and illustrated embodiment also includes means of a conventional nature for effecting manual throwon and throwoff of the blanket cylinder. This means is shown in FIGS. 1 and 2 and comprises respective gear segments 150 fixed to shafts 34, 71, respectively, and meshed with a corresponding gear 151 fixed to shafts 152 rotatably supported by the press frame adjacent the shafts 34, 711. The shafts 152 are each manually rotatable to rock the bell crank lever 33 and the rocker member 70, respectively, and effect throwoff or throwon of the blanket cylinder with respect to the corresponding cylinder. The near ends of the shafts 152, as viewed in FIG. 1, are provided with cross holes into which may be inserted pins for obtaining the necessary leverage to operate the shafts 34 and 71 manually.

From the above description, it is apparent that the throw pins 47, 48 are reciprocated in timed relation but independently of each other. Since the pins 47, 48 are not reciprocated as a unit, as has heretofore been the practice, the reciprocations of the throw pins may be out of phase and this enables the throwoff and throwon movements of the blanket cylinder 11 with respect to the plate cylinder 10 to be or to occur over nonident-ical portions of the press cycle which overlap each other. As pointed out hereinbefore, the throw pin 48 which effects the throwon movement of the cylinder 11 with respect to the cylinder 10 is preferably reciprocated so that it begins its outward movement in each press cycle in advance of the time that the leading edges of the gaps pass each other and completes the outward movement to complete the throwon of the blanket cylinder with respect to the plate cylinder when the gaps are in registry with each other. On the other hand, the throw pin 47 for effecting the throwoff movement of the blanket cylinder with respect to the plate cylinder starts its inward movement, which is the movement effective to cause throwoff, immediately after the leading edges of the gaps have passed and completes the throwoff movement after the trailing edges of the gaps have passed each other. The amount of throwoff accomplished at the time the trailing edges of the gaps pass each other is such that the blanket and the plate cylinders 10, 11 are clear of each other. It can be seen, therefore, that in the broader aspects of the present invention, mechanism is provided where the portions of the press cycle allotted to throwoif and throwon of the blanket cylinder with respect to a cooperating cylinder may and preferably do overlap each other even though constituting nonidentical portions of the press cycle.

It will be understood that the reciprocation of the throw pins 72, '74 for effecting the throwon movements and throwolf movements of the shift bar 30 and the blanket cylinder 11 from the impression cylinder 12 is preferably similar to that for the throw pins 47, 43 to effect throwoif and throwon of the blanket cylinder from or to the impression cylinder in the same manner as it is thrown off or on to the plate cylinder.

In the illustrated embodiment, the cylinder gaps are 60 gaps and throwoif starts after the leading edges of the gaps in the two cylinders pass each other and occurs for 100 of the press cycle, and throwon starts 45 before the leading edges of the gaps register and also takes place over 100 of the press cycle. The cam portion 460 and the corresponding cam portion of cam '77 for effecting the work stroke movement of the corresponding throw pins and the throwon and throwoff movements is engaged by the cam followers for 115 of cam rotation and the throw of the portion produces, in the illustrated embodiment, from .0300" to .0500" of throwoff. It will be recalled that in the first 15 of the cam portion the, the throw pins are not in engagement with their corresponding shoulders and, therefore, the actual throwon and throwoff movements occur, in the illustrated embodiment, over approximately 100 of the press cycle. The illustrated linkage may be such that only about one-third of the throwofi movement occurs over the first 45 of the "portion of press cycle where the throwoff follower is in engagement with the cam portion 450 of cam 46 or the corresponding portion of the cam 77. This will provide sufficient clearance When the trailing edges of the gaps pass each other to prevent transfer between the cylinders being thrown off.

In the illustrated embodiment, a single cam has been utilized to effect the reciprocation of the throw pins for actuating the throwolf mechanism for throwing off one cylinder with respect to the other. It will be understood that separate cams may be used to effect reciprocation of the throw pins 47, 48 for actuating the throwoif mechanism to respectively efiect the throwoif movements and the throwon movements of the blanket cylinder 1 1 with respect to the plate cylinder 10. It will be further understood that the throwolf mechanism for throwing the blanket cylinder with respect to the plate cylinder includes the shift bar 31 and those parts operatively connecting the shift bar 31 to effect a throwing off or a throwing on of the blanket cylinder and that the throw pins 47, 48 are operating members of the mechanism to which the mechanism is selectively responsive for effecting the throwoff and throwon movements, respectively.

While the preferred embodiment of the present invention has been described in considerable detail, it is hereby my intention to cover all modifications, constructions and arrangements which fall within the ability of those skilled in the art and within the scope and spirit of the present invention.

Having thus described my invention, what I claim is:

1. In a printing press having a first cylinder supported for throwoff and throwon movements with respect to a second cylinder and a cylinder throwoff mechanism for effecting said movements comprising first and second elements repeatedly operated in work strokes in timed relation to the operation of said press and means selectively responsive to the Work strokes of said first and second elements to respectively effect the throwon and throwoff movements of said first cylinder, said cylinders having gaps which extend a predetermined number of degrees about the periphery of the cylinders and which register with each other upon the rotation of the cylinders, the improvement which comprises means supporting said elements for movement independently of each other, and cam means rotated in timed relation to the operation of the press and operatively connected to each of said elements for actuating the latter through their work strokes over predetermined nonidentical portions of the press cycle, the number of degrees of rotation of said cylinders during said portions being greater than the number of degrees of said cylinder gaps and said cam means comprising first and second individual cam followers operatively connected to respective ones of said elements and a single cam rotated to actuate said followers, said followers engaging said cam at spaced points on the periphery thereof and operatively connected to said elements to actuate said elements in their work strokes by the same portion of said cam.

2. In a printing press, the structure as defined in claim 1 wherein the work strokes of said elements are in opposite directions and said elements are carried by respective rocker members, each of said rocker members being rockable about an axis and supporting a respective one of said elements, the follower and element carried by one of said rocker members being on different sides of the rocking axis thereof and the follower and element carried by the other rocker member being on the same side of the rock ing axis thereof.

3. In a printing press having a first cylinder supported for throwoif and throw on movements with respect to a second cylinder, said cylinders having gaps extending a predetermined number of degrees along the peripheries thereof and adapted to register with each other on rotation of said cylinders, and cylinder throwoff mechanism for effecting said movements comprising a throw member shiftable between first and second positions to effect the throwon and throwotf movements respectively of said first cylinder, first and second reciprocable elements selectively engageable with said throw member when moving in respective first directions to shift said throw member to respective ones of its positions, means supporting said elements for reciprocation independently of each other, and cam means for effecting reciprocation of said elements and movement of said elements in their respective first directions over predetermined, overlapping, nonidentical portions of the press cycle, the degrees of rotation of said cylinders during said portions of the press cycle being greater than said number of degrees of said cylinder gaps and said element for shifting said throw member to its first position being initiated in its said first direction before the leading edges of the gaps of said cylinders register and the element for actuating said throw member to its said second position being initiated in its first direction after the leading edges of said gaps have registered with the movement of said elements being respectively completed before and after the trailing edges of said gaps have passed registry with each other.

4. In a printing press having a first cylinder supported for throwoif and throwon movements with respect to a second cylinder and cylinder throwotf mechanism for effecting said movements comprising a first member actuatable in a first direction to a first position to effect throwon of said first cylinder and in a second direction to a second position to effect throwoff of said first cylinder, a throw member pivoted at one end to said first member, the other end of said throw member being free, and first and second reciprocable elements disposed on opposite sides of said throw member, said throw member having first and second abutment means on opposite sides thereof facing in opposite directions and being movable about its pivot to dispose the abutment means on one or the other side thereof selectively in the path of the adjacent reciprocating element when moving in one direction to move the throw member to a respective one of its said positions, said elements effecting movement of the throw member in opposite directions and the spacing of said abutment means being such that only one of said abutment means is engageable at a time by its corresponding element.

5. In a printing press, the structure as defined in claim 4 wherein said elements are supported for reciprocation independently of each other and which further comprises cam means for reciprocating said elements in out-ofphase relationship to effect movement thereof in their said one directions over predetermined nonidentical portions of the press cycle.

6. In a printing press having a first cylinder supported for throwoff and throwon movements with respect to a second cylinder and a cylinder throw mechanism including an eccentric connected to an end of the first cylinder for effecting said movements, frame means mounting said eccentric for oscillatory movement, said throw mechanism including adjusting means supported thereby and movable therewith when the throw mechanism is operated to effect said throwoif and throwon movements and relative to the throw mechanism to adjust said eccentric, operating means on the frame means for operating the adjusting means relative to the throw mechanism, and expansible drive means interconnecting the operating means and the adjusting means, said drive means being expansible between its points of connection to said operating means and to said adjusting means to enable movement of the adjusting means with the throw mechanism and relative to the operating means during the throwoif and throwon movements while maintaining the adjusted relationship of the adjusting means.

7. In a printing press as defined in claim 6 wherein the expansible drive means comprises male and female socket members capable of relative axial movement but restrained against relative rotative movement.

8. In a printing press as defined in claim 7 wherein a universal joint is positioned intermediate each the male and female socket members and the means with which each is connected.

9. In a printing press having a first cylinder supported for throwotf and throwon movements with respect to a second cylinder and a cylinder throw mechanism including an eccentric connected to an end of the first cylinder for effecting said movements, frame means mounting said eccentric for oscillation relative thereto, said throw mechanism including adjusting means for adjusting said eccentric relative to the throw mechanism and said adjusting mechanism comprising a movable member actuated relative to said frame means when said throw mechanism is operated and relative to said throw mechanism to adjust said eccentric relative to said throw mechanism and frame means, operating means on the frame means for operating said member relative to said throw mechanism, and drive means interconnecting the operating means and said member, said drive means being expansible between its points of connection to said operating means and said adjusting means to enable movement of said member upon operation of said throw mechanism while maintaining the adjusted relationship of said member relative to said throw mechanism.

10. In a printing press including a first cylinder adapted to run in engagement with second and third cylinders and inner and outer eccentrics supporting said first cylinder for throwotf and thrown on movements with respect to said second cylinder upon rotation of said eccentrics as a unit and with respect to said third cylinder upon rotation of one of said eccentrics relative to the other of said eccentrics, a toggle linkage interconnecting said eccentrics, said linkage having an on-toggle position in which the links are generally aligned in the direction of rotation of the eccentrics, stop means limiting the movement of said toggle linkage to normal positions on either side of dead center of said linkage and permitting a greater movement to one side of the center than the other, first means for selectively rotating one of said eccentrics to effect movement of both of said eccentrics as a unit, and second means operatively connected to said toggle linkage and operable to move the latter between said positions on either side of the center to move said eccentrics relative to each other, each of said first and second means comprising pairs of first and second elements, means supporting said elements of each pair for movement independently of each other, and means operatively connected to said elements and operating the latter in work strokes in timed relation to the operation of the press, said first means including means responsive to the work strokes of either the first or second elements thereof selectively to effect movement of the eccentrics operated by said first means in a respective direction and said second means including means responsive to the Work strokes of either of the first or second elements thereof selectively to move said toggle linkage to a respective one of its positions.

11. In a printing press as described in claim 10 wherein said means selectively responsive to one of said first and second elements of said second means includes a throw member actuatable to determine which one of the first and second elements of said second means to which the second means responds, and means operatively connecting said member to the ecentric actuated by said first means to move said member in one direction to render said second means responsive to one of its said elements when the eccentric is moved in one direction and to move said member in the opposite direction to render said second means responsive to the other of its elements when the eccentric is moved in the opposite direction.

12. In a printing press including a first cylinder adapted to run in engagement with second and third cylinders and inner and outer nested eccentrics supporting said first cylinder for throw off and throwon movements with respect to said second cylinder upon rotation of said eccentrics as a unit and with respect to said third cylinder upon rotation upon one of said eccentrics relative to the other of said eccentrics, a toggle linkage interconnecting said eccentrics, stop means limiting the movement of said toggle linkage to normal positions on either side of dead center of said linkage and permitting a greater movement to one side of center than to the other, first means for selectively rotating one of said eccentrics to effect movement of said ecentrics as a unit, and second means operatively connected to said toggle linkage and operable to move the latter between said positions on either side of the center to move said eccentrics relative to each other.

13. In a printing press including a first cylinder adapted to run in engagement with second and third cylinders and inner and outer eccentrics supporting said first cylinder for throwoif and throwon movements with respect to said second cylinder upon rotation of said eccentrics as a unit and with respect to said third cylinder upon rotation upon one of said eccentrics relative to the other of said eccentrics, a toggle linkage interconnecting said eccentrics comprising first and second toggle links pivoted to each other, connecting means pivotally connecting one end of each of said links to a respective one of said eccentrics, stop means limiting said toggle linkage to normal positions on opposite sides of dead center and permitting greater movement to one side of center than to the other, first means for selectively rotating one of said eccentrics in either direction to move both of said eccentrics as a unit, second means operatively connected to said toggle linkage for actuating the latter between its said positions to move said eccentrics relative to each other, the said connecting means for said first link comprising a member to which the first link is pivoted, means mounting said member on the eccentric to which said first link is connected by said connecting means for adjusting movement to vary the position of the pivot for said first link relative to the eccentric whereby the effective length of the linkage between said eccentrics and formed by said member and said links is adjusted, and means for adjusting the position of said member.

14. In a printing press including a press frame and a first cylinder adapted to run in engagement with second and third cylinders and inner and outer eccentrics supporting said first cylinder for throwotf and throwon movements with respect to'said second cylinder upon rotation of said eccentrics as a unit and with respect to said third cylinder upon rotation upon one of said eccentrics relative to the other of said eccentrics, a toggle linkage interconnecting said eccentrics comprising first and second toggle links pivoted to each other, connecting means pivotally connecting one end of each ofsaid links to a respective one of said eccentrics, stop means limiting said toggle linkage to normal positions on opposite sides of dead center and permitting greater movement to one side of center than to the other, first means for selectively rotating one of said eccentrics in either direction to move both of said eccentrics as a unit, second means operatively connected'to said toggle linkage for actuating the latter between its said positions to move said eccentrics relative to each other, the said connecting means for said first link comprising a pivot member to which the first link is pivoted, means mounting said member on the eccentric to Which said first link is connected by said connecting means for adjusting movement to vary the position of the pivot for said first link relative to the eccentric carrying said member whereby the effective length of the linkage between said' eccentrics and formed by said member and said links is adjusted, and means for adjusting the position of said member comprising a first rotatable member carried by the eccentric to which said first link is connected and connected to said pivot member to move the latter upon rotation of the first rotatable member, a second rotatable member on said frame, cooperating driving and driven members rotatable as a unit and movable axially relative to each other, a universal connection connecting the driven member to said first rotatable member and a universal connection connecting the driving member to saidsecond rotatable member for rotation thereby, and means on said frame for selectively rotating said second rotatable member.

15. In a double eccentric throwofi mechanism for throwing a first cylinder of a press oil and on with respect to cooperating cylinders and comprising inner and outer nested eccentrics supporting said cylinder and rotatably supported by the press frame for relative rotation with respect to the frame and with respect to each other, a first member carried by one of said eccentrics and rotatable relative thereto, means responsive to the rotation of said first member for adjusting said eccentrics relative to each other, a second member rotatably supported by the press frame, cooperating driving and driven members rotatable as a unit and movable axially relative to each other, first and second universal means connecting said driving and driven members to a respective one of the first and second members, and means for selectively rotating said second member.

16. In a double eccentric throwoif mechanism, the structure as defined in claim 15 wherein said means responsive to the rotation of said first member comprises a movable member movably supported by said one of said eccentrics and link means interconnecting said movable member and the other of said eccentrics, the movement of said movable member varying the effective length of the linkage between said eccentrics provided by said movable member and link means.

17. In a printing press having a first cylinder running in engagement with second and third cooperating cylinders and nested inner and outer eccentrics supporting said first cylinder for throwoif and throwon movements, said eccentrics being moved as a unit to effect the throwoff and throwon with respect to one of said cooperating cylinders and relative to each other to effect throwofi and throwon with respect to the other of said cooperating cylinders, a toggle linkage interconnecting said eccentrics, stop means limiting movement of said linkage from dead center to normal positions on either side of center with one position being farther from dead center than the other, first means for efiecting rotation of one of said eccentrics to move both of said eccentrics as a unit, second means for effecting movement of said toggle linkage between its said positions to move said eccentrics relative to each other, said first and second means each including a throw member operable in-opposite directions to effect movement of the eccentrics operated thereby in corresponding directions, and first and second elements reciprocable through work and return strokes and each being selectively engageable with said throw member when moving in a workstroke to effect shipping of said throw member in a respective one of its directions, said elements of each of said first and second means being supported for movement independently of each other and reciprocating through their Work strokes over predetermined nonidentical overlapping portions of the press cycle, means responsive to the rotation of the eccentric operated by said first means to render one of said elements of said second means effective to operate the other eccentric in a corresponding direction, and adjusting means for adjusting said eccentrics relative to each other comprising a support member movably carried by one of said eccentrics and pivotally mounting one end of said toggle linkage, a rotatable member carried by the eccentric carrying said support member, means for moving said support member in response to the rotation of said rotatable member, and means for selectively rotating said rotatable member.

18. The method of interrupting and recommencing the printing relationship of, two rotating cylinders having corresponding gaps which register with each other during each full rotation of the cylinders constituting a cycle of operation, comprising the steps of bodily commencing movement of a first one of the cylinders out of contact with the other at the time the gaps are opposed to each other along a print line established by a plane between the cylinders, completing the outward movement after the gapshave passed the print line, commencing movement of the first cylinder toward the other before the 19 gaps have reached the print line, and completing the inward movement when the gaps are in registry with each other, said cylinders being out of engagement during the ending of the outward movement and the beginning of the inward movement, and the points about the cylinders at which the outward movement begins and the inward movement ends being spaced in the gaps with the former being displaced from the middle of the gaps toward the leading edges thereof and the latter being displaced from the middle of the gaps toward the trailing edges thereof.

19. The method of interrupting and recommencing the printing relationship of two rotating cylinders having corresponding gaps which register with each other during rotation of the cylinders, comprising the steps of moving said cylinders relatively outwardly during rotation of the cylinders, and subsequently moving the cylinders inwardly into printing position while they are rotating, both of said movements taking place over a number of degrees of cylinder rotation greater than the number of degrees of the gaps and occurring over nonidentical overlapping portions of the press cycle with the initial portion of the outward movement and the ending portion of the inward movement occurring within the gaps and said cylinders being out of engagement during the ending of the outward movement and the initial inward movement.

20. In a printing press having a first rotatable cylinder supported for throwon and throwoif movements with respect to a second rotatable cylinder, said cylinders each having a gap therein which registers with the other gap upon rotation of the cylinders with each gap eXtending over the periphery of the corresponding cylinder for a predetermined number of degrees, a cylinder throwotf mechanism for effecting said movements comprising first and second elements repeatedly operated in their work strokes in timed relation to the rotation of said cylinders and means selectively responsive to the work strokes of said first and second elements to respectively effect the throwon and throwoff movements of said first cylinder, means supporting said elements for movement independently of each other, and cam means rotated in timed relation to the rotation of said cylinders and operatively connected to each of said elements for actuating the latter through their work strokes over predetermined, overlapping, nonidentical portions of each cycle of rotation of said cylinders with the work strokes of said first and second elements respectively being initiated before and after the leading edges of the gaps meet, said cam means actuating said elements through work strokes which occur over a number of degrees of rotation of said cylinders greater than said predetermined number of degrees of said gaps to effect said throwon and throwoff movements of said first cylinder.

21. In a printing press having a first rotatable cylinder supported for throwoff and throwon movements with respect to a second rotatable cylinder, said cylinders having gaps which register with each other upon rotation of the cylinders, a cylinder throwofi mechanism for effecting said movements comprising first and second elements repeatedly operated in work strokes in timed relation to the rotation of said cylinders and means selectively responsive to the work strokes of said first and second elements to respectively effect the throwon and throwofi movements of said first cylinder, means supporting said elements for movement independently of each other, cam means rotated in timed relation to the rotation of said cylinders and operatively connected to each of said elements for actuating the latter through their work strokes over different but overlapping portions of each cycle of rotation of said cylinders with the work stroke of said first element being initiated before the leading edges of said gaps pass each other and with the work stroke of said second element being initiated after the leading edges of said gaps pass each other and with said work strokes of said first and second elements being completed respectively before and after said gaps lose registry with each other.

22. In a printing press as defined in claim 21 wherein said cam means is timed to complete the work stroke of said first element immediately prior to the passage of the trailing edges of said gaps and to initiate the work stroke of said second element immediately after the passage of the leading edges of said gaps.

23. In a printing press as defined in claim 21 wherein said cam means comprises first and second individual cam followers operatively connected to respective ones of said elements.

24. A method of interrupting and recommencing the printing relationship of two rotating cylinders having corresponding gaps which register with each other during a predetermined angular portion of each full rotation of the cylinders constituting a cycle of operation comprising the steps of bodily moving a first one of the cylinders into and out of printing relationship with the other cylinder to effect throwon and throwotf of the cylinders with the movement out of printing relationship being initiated while the gaps are opposite to each other at the printing line and being completed after the gaps have passed each other and with the movement of the first cylinder into printing relationship being initiated at a point in the angular rotation of said cylinders in advance of the point that the throwoff movement is initiated and is completed after the point at which the throwoff movement is initiated and at a point in the angular rotation of the cylinder before the trailing edges of the gaps pass each other.

25. In a printing press having a first rotatable cylinder supported for throwoff and throwon movements with respect to a second rotatable cylinder, said cylinders having gaps which register with each other upon the rotation of the cylinders, a cylinder throwofi mechanism for effecting said movements comprising first and second elements repeatedly operated in work strokes in timed relation to the operation of said cylinders and means selectively responsive to the work strokes of said first and second elements to respectively effect the throwon and throwoff movements of said first cylinder, means supporting said elements for movement independently of each other, cam means rotated in timed relation to the rotation of said cylinders and operatively connected to each of said elements for actuating the latter through their work strokes over different but overlapping portions of each cycle of rotation of said cylinders with the work stroke of said second element being initiated during the rotation of said cylinders at a predetermined angular position of said cylinders in which said cylinders are in registry with each other and in advance of a second position of said cylinders where the trailing edges of said gaps are in registry and with the work stroke of said first element being initiated at an angular position in advance of said predetermined angular position and completed at an angular position of said cylinders following said predetermined angular position and before said second angular position, the work stroke of said second element being completed at a position following said second angular position.

26. In a printing apparatus having two rotating cylinders, corresponding gaps in said cylinders which register with each other during a predetermined angular portion of each full rotation of the cylinders constituting a cycle of operation, and operating means for bodily moving a first one of said cylinders out of and into printing relationship with the second one of said cylinders, the improvement comprising power actuated means for moving said operating means in throwon and throwoff movements at least one of which occurs over an angle of rotation of said cylinders greater than the circular extent of said gaps including means timing the operation of said power actuated means to begin movement of said first one of said cylinders bodily out of printing relationship while said gaps are opposite to each other at the printing line and to complete said movement after said gaps have passed each other and to begin movement of said first one of said cylinders into printing relationship at a point in the angular rotation of said cylinders in advance of the point at which movement of said first one of said cylinders out of printing relationship began and to complete said movement after the point at which movement of said first one of said cylinders out of printing relationship began and before the trailing edges of said gaps pass each other.

References Cited in the file of this patent UNITED STATES PATENTS Niles Aug. 1, 1916 Harrold Apr. 27, 1926 Wood Dec. 11, 1956 Royer Sept. 30, 1958 Fowlie Nov. 18, 1958 

